Laars NEOTHERM NTH Series, Инструкция по установке и эксплуатации

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LAARS Heating Systems
Outdoor Reset Functions -
The next four lines in the display are used to set up the
Outdoor Reset functions:
• Outdoor Reset Enable/Disable - Note: This function
can be Enabled/Disabled only by a factory trained
technician.
• Low Water Temperature - Use the Up- and Down-
Buttons to select the function, use Up- and Down- to
select the new value, then press the round OK button.
• Maximum Outdoor Temperature - Use the Up- and
Down-Buttons to select the function, use Up- and
Down- to select the new value, then press the round
OK button.
• Minimum Outdoor Temperature - Use the Up- and
Down-Buttons to select the function, use Up- and
Down- to select the new value, then press the round
OK button.
For a complete explanation of the setup for Outdoor
Reset, see Section 8C.5.
Adjustable High Limit -
The absolute high limit setting for the water outlet
temperature for this unit is set at the factory to 195°F
(90.5°C). If you wish, you can also set a second or
“adjustable” limit setting that is lower.
Use the Up- and Down-Buttons to select the function, use
Up- and Down- to select the new value, then press the
round OK button.
Adjustable Stack Limit -
The absolute high limit setting for the stack for this unit is
set at the factory to 195°F (90.5°C). If necessary, you can
set the unit to use a second or “adjustable” limit setting
that is lower.
Use the Up- and Down-Buttons to select the function, use
Up- and Down- to select the new value, then press the
round OK button.
8.G 24 VAC Transform with Integral Circuit
Breaker
24 VAC is supplied by a transformer mounted underneath
the control panel. All 24 VAC power is supplied through
a circuit breaker that is part of the transformer. The
transformer is then connected to terminal blocks 3 and 4
(TB3 and TB4).
See Figure 30.
8.H Hydronic Heating Demand
When using the unit for hydronic heating, a call for heat
must be supplied to the “T-T or Interlock” terminal. Once
the call is supplied, the control starts the Boiler and
System pumps, and begins the ignition process. The
ignition process consists of a prepurge, trial for ignition,
and run period. The prepurge period starts on a call for
heat once the fan RPM reaches a preset level. The trial
for ignition period follows once the start-up RPM of the
fan has been reached. The trial for ignition period lasts
four seconds, During this period the direct spark ignition
system and gas valve are energized. At the end of the trial
for ignition period, the flame signal is compared with the
preset flame threshold value. If the flame signal is higher
than the flame threshold, the Unit enters Run. If the flame
signal is below the threshold, the Unit returns to prepurge
and starts the ignition process over. When operating in
Run, the Unit monitors the flame signal, call for heat input,
safety switches, and water temperatures and modulates as
needed between 100% and 20% of rate to satisfy the call
for heat.
Connect the call for heat to terminal block 7 (TB7), See
Figure 30 , connections labeled “T-T or interlock” in the
control panel.
The CH Setpoint can be set from the Quick Start menu.
How to get there: From the “Home” screen, press “I” to
go to “Info/ Install.” Choose “Quick Start,” then go to “CH
Setpoint.”
8.I
Anti-Short-Cycle (ASC)
The anti short cycle function helps to prevent short-cycling
when the call for heat switches on and off quickly.
To reach the anti-short-cycle function, select Info/ Advanced
Setup/ System Config./ System Config.
How to get there: From the “Home” screen, press “I”
to go to “Info/ Install.” Choose “Advanced Setup,” then
“System Configuration,” then “System Configuration”
again.
Configuration and Setup